Method for producing electronic part package

ABSTRACT

A peeling off layer  18  is formed on an entire surface of one surface side of a support plate  10  including the inner wall surfaces respectively of a recessed part  12  for an electronic part and recessed parts  16  for posts in which the posts  20  are formed. Then, the recessed parts  16  are filled with metal to form the posts  20 . Then, conductor patterns  28  are formed that electrically connect the electrode terminals  22   a  of the electronic part  22  inserted into the recessed part  12  to the posts  20 . Then, an insulating layer covering the conductor patterns  28  is formed to form an electronic part package  30  on the one surface side of the support plate  10  through the peeling off layer  18 . After that, the electronic part package  30  is separated from the support plate  10  by the peeling off layer  18.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 U.S.C. §119from Japanese Patent Application No. 2008-228204 filed on Sep. 5, 2009.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a method for producing an electronicpart package, and more particularly to a method for producing anelectronic part package in which electrode terminals of a mountedelectronic part are electrically connected to posts as externalconnecting terminals by electrically conductive patterns.

2. Related Art

An electronic part such as a semiconductor element has beenprogressively thinned in order to miniaturize a mounting device on whichthe electronic part is mounted. Accordingly, as for an electronic partpackage on which the electronic part is mounted, the thin electronicpart package has been requested similarly to the electronic part mountedthereon.

To meet such a demand, U.S. Pat. No. 6,586,822 proposes a method forproducing an electronic part package having the same thickness as thatof mounted electronic part.

The method for producing the electronic part package proposed in U.S.Pat. No. 6,586,822 is shown in FIG. 9. In the method for producing theelectronic part package shown in FIG. 9, as shown in FIG. 9( a), athrough hole 102 is opened at a prescribed position of a resin plate 100having the same thickness as that of the mounted electronic part, andthen, a resin film 104 is stuck to one surface side of the resin plate100.

An electronic part 106 is inserted into the through hole 102 having oneside of an opening part covered with the resin film 104 in such a way asshown in FIG. 9( b). At this time, the electronic part 106 is insertedso that electrode terminals 106 a, 106 a, . . . of the electronic part106 are located in the resin film 104 side.

Gaps 102 a between the inserted electronic part 106 and the through hole102 are filled with a resin 108 as shown in FIG. 9( c) to fix theelectronic part 106 in the through hole 102.

Then, conductor patterns 114 are laminated through resin layers 110 by,what is called a build-up method (FIG. 9 f)) in which as shown in FIG.9( d), on the resin layer 110 that covers en entire surface of onesurface side of the resin plate 100 from which the resin film 104 ispeeled off, recessed parts 112 are formed in which the electrodeterminals 106 a of the electronic part 106 are exposed on bottomsurfaces, and then, as shown in FIG. 9( e), the conductor patterns 114is formed that are electrically connected to the electrode terminals 106a exposed on the bottom surfaces of the recessed parts 112.

According to the method for producing the electronic part package shownin FIG. 9, the thin electronic part package having the same thickness asthat of the electronic part can be formed.

However, in the electronic part package obtained by the method forproducing the electronic part package shown in FIG. 9, the resin plate100 is left. Therefore, the obtained electronic part package has a smallthickness, however, has a large area.

On the other hand, in a mounting device on which the electronic partpackage is mounted, an area of the electronic part package is alsorequested to be reduced for the purpose of its miniaturization.

SUMMARY OF THE INVENTION

Thus, it is an object of the present invention to provide a method forproducing an electronic part package that can solve a problem of a usualmethod for producing an electronic part package which can have the samethickness as that of a mounted electronic part, however, has a largearea, and can reduce both the thickness and the area.

When the inventors of the present invention studied whether theelectronic part package could be produced or not without using the resinplate 100 in the method for producing the electronic part package shownin FIG. 9, they found that since the electronic part 106 is formed to bethin and compact, the strength of the electronic part 106 could notendure a stress acting in a production process of the electronic partpackage.

Accordingly, the inventors of the present invention finds that theelectronic part is supported by a support plate to form the electronicpart package and the support plate is finally removed to form theelectronic part package including no support plate, and reached thepresent invention.

That is, according to a first aspect of the invention, there is provideda method for producing an electronic part package in which electrodeterminals of the electronic part to be mounted are electricallyconnected to posts as external connecting terminals by electricallyconductive patterns,

the method including the steps of:

forming a peeling off layer on an entire surface of one surface side ofa support plate with inner wall surfaces having a first recessed partthat is opened to the one surface side of the support plate and intowhich the electronic part are inserted to be positioned and secondrecessed parts in which the posts are formed,

filling the second recessed parts with an electrically conductivematerial to form the posts,

inserting the electronic part into the second recessed part;

forming the electrically conductive patterns that electrically connectthe electrode terminals of the electronic part to the posts,

forming an insulating layer covering the electrically conductivepatterns to form the electronic part package on the one surface side ofthe support plate through the peeling off layer; and

separating the electronic part package from the support plate by thepeeling off layer.

According to a second aspect of the invention, there is provided themethod for producing an electronic part package of the first aspect,wherein

the first recessed part is formed by applying a sandblasting process tothe one surface side of the support plate.

In this invention, the recessed part for the electronic partcorresponding to the inserted electronic part can be easily formed.

According to a third aspect of the invention, there is provided themethod for producing an electronic part package of the first or secondaspect, wherein

the support plate is made of silicon or glass.

Then, the electronic part can be assuredly supported.

Further, according to a fourth aspect of the invention, there isprovided the method for producing an electronic part package of thefirst aspect, wherein

the support plate is made of silicon, and

the first recessed part and the second recessed parts are respectivelyformed by a dry etching process.

Further, according to a fifth aspect of the invention, there is provideda method for producing an electronic part package in which electrodeterminals of electronic part to be mounted are electrically connected toposts as external connecting terminals by electrically conductivepatterns,

the method including the steps of:

forming a first insulating layer having a thickness same as a thicknessof the electronic part on a seed layer made of metal and formed on onesurface side of a support plate through a peeling off layer,

forming, on the first insulating layer, a first recessed part with asize in which the electronic part is inserted to be positioned and theseed layer is exposed on a bottom surface and second recessed parts inwhich the seed layer is exposed on bottom surfaces and the posts areformed;

filling the second recessed parts with an electrically conductivematerial to form the posts,

inserting the electronic part into the first recessed part,

forming the electrically conductive patterns that electrically connectthe electrode terminals of the electronic part to the posts;

forming a second insulating layer that covers the electricallyconductive patterns to form the electronic part package in the onesurface side of the support plate through the peeling off layer,

separating the seed layer from the support plate by the peeling offlayer; and

removing the seed layer and the first insulating layer adhering to theelectronic part package.

According to a sixth aspect of the invention, there is provided themethod for producing an electronic part package of the fifth aspect,wherein

the support plate is made of silicon or glass.

Then, the electric parts can be assuredly supported.

According to a seventh aspect of the invention, there is provided themethod for producing an electronic part package of any one of the firstto sixth aspects, wherein

the support plate separated from the electronic part package is usedagain as a support plate.

In the present invention, while the electronic part are supported by thesupport plate, the electronic part package can be produced. Thus, thedeformation of the electronic part can be avoided.

Further, since the electronic part package is formed in one surface sideof the support plate through the peeling off layer, the support platecan be separated from the electronic part package. Accordingly, thesupport plate can be separated from the electronic part package moresimply and in a shorter time than a case that the support plate ismelted and removed by an etching process.

In such a way, since the support plate required in a production processof the electronic part package can be separated from the electronic partpackage, the obtained electronic part package can be formed to be thinand have a small area.

Further, in the present invention, the recessed part with the size intowhich the electronic part can be inserted and positioned is formeddirectly on the support plate or on the first resin layer formed on thesupport plate. Therefore, the electrode terminals of the electronic partinserted into the recessed part can be accurately positioned and thedisplacement of the electrode terminals of the conductive patternsconnected thereto can be prevented. As a result, a reliability of theobtained electronic part package can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1( a) to 1(c) are process diagrams that explain a part ofprocesses in one example of a method for producing an electronic partpackage according to the present invention.

FIGS. 2( a) to 2(f) are process diagrams that explain processessubsequent to the processes shown in FIGS. 1( a) to 1(c) in one exampleof the method for producing an electronic part package according to thepresent invention.

FIGS. 3( a) to 3(c) are process diagrams that explain remainingprocesses in one example of the method for producing an electronic partpackage according to the present invention.

FIGS. 4( a) and 4(b) are process diagrams that explain another exampleof a method for producing an electronic part package according to thepresent invention.

FIGS. 5( a) to 5(d) are process diagrams that explain a part ofprocesses in other example of a method for producing an electronic partpackage according to the present invention.

FIGS. 6( a) to 6(e) are process diagrams that explain remainingprocesses in other example of the method for producing an electronicpart package according to the present invention.

FIG. 7 is an explanatory view explaining a state that the electronicpart package obtained by the method for producing an electronic partpackage shown in FIGS. 5 and 6 is mounted on a mounting substrate.

FIG. 8 is an explanatory view explaining a state that a plurality ofelectronic part packages obtained by other example of the method forproducing an electronic part package according to the present inventionare laminated.

FIGS. 9( a) to 9(f) are process diagrams that explain processes of ausual method for producing an electronic part package.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

One example of a method for producing an electronic part packageaccording to the present invention is shown in FIGS. 1 to 3. In themethod for producing the electronic part package, as shown in FIG. 1(a), on one surface side of a support plate 10 made of silicon or glass,a recessed part 12 for an electronic part (refer it to as a recessedpart 12, hereinafter) is formed that has a size into which asemiconductor element as the electronic part is inserted and positionedand a thickness equal to the thickness of the inserted semiconductorelement. The recessed part 12 is formed by forming an opening part inwhich the one surface side of the support plate 10 is exposed at aprescribed position of a dry film 14 stuck to the one surface side ofthe support plate 10, and then applying a sandblasting process.According to the sandblasting process, the recessed part 12 can beaccurately formed to meet the form of the inserted semiconductorelement.

Further, as shown in FIG. 1( b), in peripheral edge sides of the supportplate 10 from the recessed part 12, recessed parts 16 and 16 for posts(occasionally refer them as recessed parts 16, hereinafter) are formedwhose depth is larger than that of the recessed part 12. The recessedparts 16 are also formed by forming opening parts in which the onesurface sides of the support plate 10 are exposed at prescribedpositions of a dry film 15 stuck to the one surface side of the supportplate 10, and then applying a sandblasting process.

The dry film 15 is peeled off from the one surface side of the supportplate 10 including the inner peripheral walls of the recessed part 12and the recessed parts 16 and 16 to form a peeling off layer 18 on anentire surface of the one surface side of the support plate 10 as shownin FIG. 1( c). The peeling off layer 18 is made of metal and is formedwith a layer 18 a made of titanium or chromium, a tin layer 18 b and acopper layer 18 c from the one surface side of the support plate 10 asshown in an enlarged diagram. In the peeling off layer 18, a boundarysurface between the layer 18 a made of titanium or chromium and the tinlayer 18 b is liable to be peeled off. The peeling off layer 18 can beobtained by sequentially laminating prescribed metal layers by asputtering process, a deposition process, an electro-less platingprocess or an electrolytic plating process.

As the peeling off layer 18, a peeling off layer may be employed inwhich the copper layer is added between the layer 18 a made of titaniumor chromium and the tin layer 18 b, that is, a peeling off layer may beemployed in which the layer made of titanium or chromium, the copperlayer, the tin layer and the copper layer are sequentially laminatedfrom the one surface side of the support plate 10.

In the recessed parts 16 and 16 formed in the one surface side of thesupport plate 10, as shown in FIG. 2( a), parts of a dry film 17covering the one surface side of the support plate 10 that correspond tothe recessed parts 16 and 16 are opened, and then, an electrolyticcopper plating process is applied thereto by using the metallic peelingoff layer 18 as a feeding layer to fill the recessed parts 16 and 16with copper and form posts 20 and 20. The shape of the post 20 may be acone or a pyramid, thereby it is easier to separate the support plate10.

After the dry film 17 is peeled off, as shown in FIG. 2( b), asemiconductor element 22 is inserted into the recessed part 12. Therecessed part 12 is formed with such a size as to position thesemiconductor element 22 and with a depth equal to the thickness of thesemiconductor element 22. Therefore, the semiconductor element 22inserted into the recessed part 12 can be precisely positioned and itselectrode terminals 22 a and 22 a are also precisely positioned.

Conductor patterns are formed that connect the electrode terminals 22 aand 22 a respectively to the prescribed posts 20.

When the conductor patterns are formed, a well-known method such as whatis called an additive method or a semi-additive method can be used. InFIG. 2( c), in a resin layer 24 formed so as to cover the one surfaceside of the support plate 10, are formed recessed parts in which theposts 20 and 20 are respectively exposed on bottom surfaces and recessedparts in which the electrode terminals 22 a and 22 a of thesemiconductor element 22 are exposed on bottom surfaces. After that, athin metal layer 26 is formed on one surface of the resin layer 24 by anelectro-less copper plating process, a deposition process or asputtering process.

After a patterning process is applied to a dry film 19 stuck to the thinmetal layer 26 as shown in FIG. 2( d), an electrolytic copper platingprocess using the thin metal layer 26 as a feeding layer is appliedthereto to form the conductor patterns 28 and 28 as shown in FIG. 2(e).

Then, as shown in FIG. 2( f) the dry film 19 is peeled off to remove theexposed thin metal layer 26 by etching and insulate between theconductor patterns 28 and 28.

Further, as shown in FIG. 3( a), a part between the formed conductorpatterns 28 and 28 is sealed with a resin by the resin layer 24 to forman electronic part package 30.

When the electronic part package 30 is separated from the support plate10 by the peeling off layer 18, a part of the peeling off layer 18adheres to the electronic part package 30 as shown in FIG. 3( b).Accordingly, the peeling off layer 18 adhering to the electronic partpackage 30 is removed by etching so that the electronic part package 30shown in FIG. 3( c) can be obtained.

In the electronic part package 30, the electrode terminals 22 a and 22 aof the semiconductor element 22 and the posts 20 whose thickness islarger than the thickness of the semiconductor element 22 arerespectively electrically connected by the conductor patterns 28 sealedby the resin layer 24.

In the electronic part package 30 shown in FIG. 3( c) since the supportplate 10 is not left, when the semiconductor element 22 having thethickness of about 20 μm is used as the semiconductor element 22, athickness H from the upper surface of the resin layer 24 to the lowerend of the post 20 can be set to about 100 μm so that an area of theelectronic part package 30 can be decreased.

In the electronic part package shown in FIG. 3( c) any parts cannot beprovided in an upper surface side. However, in a process shown in FIG.3( a), via parts 32 are formed with one ends connected to the conductorpatterns 28 and the other ends exposed to the upper surface side of theresin layer 24 as shown in FIG. 4( a). Thus, as shown in FIG. 4( b),other electronic part 34 can be mounted on the upper surface side of theelectronic part package 30. As other electronic part 34, active partssuch as the semiconductor element and passive parts such as a capacitorcan be employed.

Since the support plate 10 separated from the electronic part package 30is formed with silicon or glass, the support plate 10 can be used againas the support plate 10.

In the method for producing the electronic part package shown in FIGS. 1to 4, the recessed parts 12 and 16 are formed on the support plate 10,however, a producing method is shown in FIGS. 5 to 6 that can obtain anelectronic part package without forming the recessed parts 12 and 16 onthe support plate 10.

Initially, a seed layer 44 made of metal is formed on one surface sideof a support plate 40 made of silicon or glass through a peeling offlayer 42. The peeling off layer 42 is a peeling off layer formed with aresin. As the resin, an acrylic resin, a novolak type phenol resin, HMDS(hexamethyl silazane) or the like can be preferably used. Further, theseed layer 44 can be formed by combining together an electro-lessplating process, a sputtering process, a electrolytic plating process, adeposition process or the like.

On the seed layer 44, as shown in FIG. 5( b), a first resin layer 46having the same thickness as that of a semiconductor element as amounted electronic part is formed, and then, recessed parts 52 for posts(occasionally refer them to as recessed parts 52, hereinafter) areformed in which the seed layer 44 is exposed on bottom surfaces andposts are formed. Further, the recessed parts 52 are filled with copperby an electrolytic copper plating process using the seed layer 44 as afeeding layer to form posts 54.

Then, a recessed part 50 for the electronic part (occasionally refer itto as a recessed part 50, hereinafter) is formed in which the seed layer44 is exposed on a bottom surface and the semiconductor is inserted. Therecessed part 50 has substantially the same area as that of the insertedsemiconductor element and has a depth equal to the thickness of thesemiconductor element so as to position the inserted semiconductorelement. Accordingly, as shown in FIG. 5( b), the semiconductor element56 inserted into the recessed part 50 can be accurately positioned andits electrode terminals 56 a and 56 a can be also accurately positioned.

Conductor patterns are formed that connect the electrode terminals 56 aand 56 a respectively to the prescribed posts 54.

When the conductor patterns are formed, a well-known method such as whatis called an additive method or a semi-additive method can be used. InFIG. 5( c), in a second resin layer 58 formed so as to cover the onesurf ace side of the support plate 40, are formed recessed parts inwhich the posts 54 and 54 are respectively exposed on bottom surfacesand recessed parts in which the electrode terminals 56 a and 56 a of thesemiconductor element 56 are exposed on bottom surfaces. After that, athin metal layer 60 is formed on one surface of the second resin layer58 by an electro-less copper plating process, a deposition process or asputtering process as shown in FIG. 5( d).

After a patterning process is applied to a dry film 62 stuck to the thinmetal layer 60 as shown in FIG. 6( a) an electrolytic copper platingprocess using the thin metal layer 60 as a feeding layer is appliedthereto to form the conductor patterns 64 and 64 as shown in FIG. 6( a).

Then, as shown in FIG. 6( b), the dry film 62 is peeled off to removethe exposed thin metal layer 60 by etching and insulate between theconductor patterns 64 and 64.

Further, as shown in FIG. 6( c), the formed conductor patterns 64 and 64are sealed with a resin by the second resin layer 58 to form anelectronic part package 70.

The electronic part package 70 is separated from the support plate 40 asshown in FIG. 6( d). When the electronic part package 70 is separatedfrom the support plate 40, if the peeling off layer 42 is formed withthe acrylic resin, the peeling off layer 42 is heated to 180° C. orhigher so that the support plate 40 can be separated. If the peeling offlayer 42 is formed with the novolak type phenol resin, the support plate40 can be separated by using a peeling off liquid.

When the electronic part package 70 is separated from the support plate40, the seed layer 44 adheres to the electronic part package 70 as shownin FIG. 6( d). Accordingly, the seed layer 44 adhering to the electronicpart package 70 is removed by etching, and then, the first resin layer46 is removed so that the electronic part package 70 shown in FIG. 6( e)can be obtained.

In the electronic part package 70, the electrode terminals 56 a and 56 aof the semiconductor element 56 and the posts 54 whose thickness isequal to the thickness of the semiconductor element 56 are respectivelyelectrically connected by the conductor patterns 64 sealed by the secondresin layer 58.

In the electronic part package 70 shown in FIG. 6( e) since thesemiconductor element 56 has the same thickness as that of the posts 54,when the electronic part package is mounted on a mounting substrate,pads 66 and 66 having a prescribed height and connected to the posts 54and 54 are formed on the mounting substrate 68 as shown in FIG. 7.

Further, as shown in FIG. 8, a plurality of electronic part packages 70,70, . . . can be laminated. In this case, on the electronic partpackages 70 respectively, pads 74 of a prescribed height are formed onthe other end sides of via parts 72 that pass thorough the second resinlayers 58 and have one ends connected to the conductor patterns 64.

As the support plate 10 or 40 shown in FIGS. 1 to 6, the support platemade of silicon or glass is used, however, a support plate made ofstainless steel, copper, a glass epoxy resin or ceramic may be employed.

Further, when the recessed parts 16, 12, 50 and 52 are formed in thesupport plates 10 and 40, the recessed parts are formed by asandblasting process, however, the recessed parts may be formed by a wetetching or a dry etching or a machining work. Especially, the supportplate 10 made of silicon is preferably employed as the support plate 10to form the recessed part 12 for the electronic part and the recessedparts 16 for the posts respectively by the dry etching using SF₆ gas orCF₄ gas.

Further, a plurality of recessed parts 12 and 50 for electronic partsmay be formed on the support plates 10 and 40 to form an electronic partpackage provided with the plurality of recessed parts into which theplurality of electronic parts are inserted.

The recessed parts 16 and 52 are filled with metal, however, therecessed parts may be filled with an electrically conductive resin.

1. A method for producing an electronic part package in which electrodeterminals of the electronic part to be mounted are electricallyconnected to posts as external connecting terminals by electricallyconductive patterns, the method comprising the steps of: forming apeeling off layer on an entire surface of one surface side of a supportplate with inner wall surfaces having a first recessed part that isopened to the one surface side of the support plate and into which theelectronic part are inserted to be positioned and second recessed partsin which the posts are formed, filling the second recessed parts with anelectrically conductive material to form the posts, inserting theelectronic part into the second recessed part; forming the electricallyconductive patterns that electrically connect the electrode terminals ofthe electronic part to the posts, forming an insulating layer coveringthe electrically conductive patterns to form the electronic part packageon the one surface side of the support plate through the peeling offlayer; and separating the electronic part package from the support plateby the peeling off layer.
 2. The method for producing an electronic partpackage of claim 1, wherein the first recessed part is formed byapplying a sandblasting process to the one surface side of the supportplate.
 3. The method for producing an electronic part package of claim1, wherein the support plate is made of silicon or glass.
 4. The methodfor producing an electronic part package of claim 1, wherein the supportplate is made of silicon, and the first recessed part and the secondrecessed parts are respectively formed by a dry etching process.
 5. Amethod for producing an electronic part package in which electrodeterminals of electronic part to be mounted are electrically connected toposts as external connecting terminals by electrically conductivepatterns, the method comprising the steps of: forming a first insulatinglayer having a thickness same as a thickness of the electronic part on aseed layer made of metal and formed on one surface side of a supportplate through a peeling off layer, forming, on the first insulatinglayer, a first recessed part with a size in which the electronic part isinserted to be positioned and the seed layer is exposed on a bottomsurface and second recessed parts in which the seed layer is exposed onbottom surfaces and the posts are formed; filling the second recessedparts with an electrically conductive material to form the posts,inserting the electronic part into the first recessed part, forming theelectrically conductive patterns that electrically connect the electrodeterminals of the electronic part to the posts; forming a secondinsulating layer that covers the electrically conductive patterns toform the electronic part package in the one surface side of the supportplate through the peeling off layer, separating the seed layer from thesupport plate by the peeling off layer; and removing the seed layer andthe first insulating layer adhering to the electronic part package. 6.The method for producing an electronic part package of claim 5, whereinthe support plate is made of silicon or glass.
 7. The method forproducing an electronic part package of claim 1, wherein the supportplate separated from the electronic part package is used again as asupport plate.
 8. The method for producing an electronic part package ofclaim 5, wherein the support plate separated from the electronic partpackage is used again as a support plate.
 9. The method for producing anelectronic part package of claim 1, further comprising: a via partformed with one end thereof connected to the conductive patterns and theother end thereof exposed to an upper surface side of the insulatinglayer.
 10. The method for producing an electronic part package of claim5, further comprising: a via part formed with one end thereof connectedto the conductive patterns and the other end thereof exposed to an uppersurface side of the insulating layer.
 11. The method for producing anelectronic part package of claim 1, wherein the peeling off layerincludes a layer made of titanium or chromium, a tin layer and a copperlayer from the one surface side of the support plate.
 12. The method forproducing an electronic part package of claim 5, wherein the peeling offlayer includes a layer made of titanium or chromium, a tin layer and acopper layer from the one surface side of the support plate.
 13. Themethod for producing an electronic part package of claim 1, wherein ashape of the post is a cone or a pyramid.
 14. The method for producingan electronic part package of claim 5, wherein a shape of the post is acone or a pyramid.